I started a Scottish Ale on the 19th, in the excitment I forgot to really oxygenate it, I thought about it only 24 hours later

Anyway, after about 12 hours the fermentation started, the OG was 1.050 and the pitching temp was 24C. My yeast was a Wyeast Activator Scotch Ale pack. My current temp is 20.5C. And the current gravity is 1.038.

Do you think it's really too slow? Should I do something? Rack for giving oxygen to the yeast? Is it fine as is?

I don't think it's a particularly slow fermentation.
You pitched on the 19th, it didn't start until the 20th, and it's only the 23rd. I assume it's still fermenting...

The best thing to do at this point is probably to let it go. It's kind of late to add oxygen and racking it off the yeast is the last thing you want to do. I think it will be best to leave it alone, allow it to finish fermenting, then give it a few more days to clean up any fermentation byproducts that might have been made due to the stressed fermentation.

A week isn't an unusual amount of time for a fermentation to completely finish. Two weeks isn't a bad amount of time to let it sit before racking.

jmorignot wrote:And do you think I will have enough active yeast for the carbonation?

I don't think there should be any problem with that.

You need to age more on the terms of months and usually at low temperatures and with very clean transfers before not having enough yeast is a concern. It may take a week or so longer to fully carbonate, but you'll have the payoff of having less yeast on the bottom of the bottle.

It sounds like it might be time to try adding more yeast. You could probably add US-05 without altering the flavor profile much. It's a pretty aggressive fermenter, so if there are some edible sugars around it should eat them.

I've never had a stuck fermentation myself, but I've read that it can be difficult to get the added yeast to ferment a partially fermented beer. What some say helps, is making a small starter to get the yeast going, then adding the yeast once it begins actively fermenting, which should only take a few hours. While it is active, it's more apt to keep fermenting in the beer. It's a variation on Kreusening.

Normally, I wouldn't recommend a starter for dry yeast, but this might be an exception.

i used 1728 scottish ale, didnt make a starter and had a almost 3 day lag before the primary kicked off....... my fault, i added a lager yeast after about a week and it took off again in the secondary within 4 hours, try the 05 yeast and you should be fine.